狭翅雏蝗发育起点温度和有效积温的研究

在室外自然条件下用无芒雀麦（Ｂｒｏｍｕｓｉｎｅｒｍｉｓ）叶片饲喂狭翅雏蝗Ｃｈｏｒｔｈｉｐｐｕｓｄｕｂｉｕｓ（Ｚｕｂｏｖｓｋｙ）Ｕｖｒｏｖ，分别以直线回归法和直接最优法计算发育起点温度和有效积温，并与实际发生情况作了初步验证。全蝗蝻期发育起点温度为９．１７℃（直线回归法）或９．４１℃（直接最优法），有效积温为１９０．７０日度（直线回归法）或１７５．４４日度（直接最优法）。测定结果直接最优法计算结果较直线回归法更切合实际。     

狭翅雏蝗蝗蝻抽样技术的研究

本文在空间格局研究的基础上,对狭翅雏蝗蝗蝻在不同密度下的理论抽样数及序贯抽样技术进行了研究。结果表明：狭翅雏蝗蝗蝻的理论抽样数可据ｎ＝（１／Ｄ２）（１２７５６／ｍ＋０３６１８）确定,序贯抽样可依Ｉｗａｏ法确定的两条截止线Ｔｏ（ｎ）＝８０７５ｎ±１１４１０５ｎ和据Ｋｕｎｏ确定的最大抽样数Ｔｎ＝１２７５６／（Ｄ２－０３６１８／ｎ）结合起来使用。     

狭翅雏蝗的种群数量消长模型

应用在甘肃省夏河县甘加高山草原的系统调查资料,对狭翅雏蝗的种群数量消长进行了模拟。结果表明, 狭翅雏蝗在草地的种群数量动态可用数学模型Nt=0.348 51t1.21333·e-0.02941t来描述。     

狭翅雏蝗种群动态的模糊聚类分析

本文作者用平均密度(M)、聚集度指标(M^*/M)、有虫样方出现频率(F),对狭翅雏蝗在草原的种群动态进行了模糊聚类分析。结果表明,狭翅雏蝗发生的动态规律可分为四个状态集。其中发生在前期末既是预测预报的关键时期,也是药剂防治的有利时机。     

狭翅雏蝗的种群数量消长模型

应用在甘肃省夏河县甘加高山草原的系统调查资料,对狭翅雏蝗的种群数量消长进行了模拟.结果表明,狭翅雏蝗在草地的种群数量动态可用数学模型Nt=0.348 51t1.213 33·e-0.029 41t来描述.     

小垫尖翅蝗蝗蝻空间分布型的初探

昆虫种群在不同虫期的密度在空间分布上有一定的差异,这给在虫害抽样调查中掌握害虫的实际密度造成了困难,为了确定防治指标和提高预测预报水平,对小垫尖翅蝗蝗蝻的空间分布型进行了初步调查及研究,以确定适宜的抽样数,保证在今后的调查工作中获得较为准确的数据。     

紫花苜蓿田短星翅蝗发生规律及防治对策

短星翅蝗是紫花苜蓿田中的主要害虫，为摸清该虫的发生规律，于1999--2002年采取了笼内饲养与大田系统调查相结合的方法，对该虫进行了调查。该虫在滨州市紫花苜蓿田1年发生1代，以卵在土中越冬，蝗蝻雌虫6个龄期，雄虫5个龄期。介绍了该虫的为害特点、年生活史、生活习性、发生与环境的关系以及防治方法。     

小垫尖翅蝗蝗蝻空间分布型的初探

昆虫种群在不同虫期的密度在空间分布上有一定的差异,这给在虫害抽样调查中掌握害虫的实际密度造成了困难,为了确定防治指标和提高预测预报水平,对小垫尖翅蝗蝗蝻的空间分布型进行了初步调查及研究,以确定适宜的抽样数,保证在今后的调查工作中获得较为准确的数据.     

紫花苜蓿田大垫尖翅蝗发生规律的研究

大垫尖翅蝗Epacromius coerulipes是紫花苜蓿Medicago sativa田的主要害虫.为摸清其发生规律,于1999-2002年采取了大田调查与笼内饲养相结合的方法,对该虫进行了调查.该虫在鲁北地区紫花苜蓿田1年发生2代,以卵在土中越冬,蝗蝻共5个龄期.并对该虫的年生活史、习性、发生与环境条件的关系进行了叙述,提出了防治策略.     

邱氏异爪蝗生物学特性的研究

通过在甘肃省夏河县的野外系统调查和饲养测表明,邱氏异爪蝗一年发生１代,以卵在土中越冬。翌年５月中旬开始孵化出土,６月上旬为孵化出土盛期。７月上旬始见虫,８月上旬成虫开始产卵。蝗蝻期共５龄,平均６９．４０天。成虫寿命平均６０．４２天。     

草原蝗虫生物学和生态学的研究

论述了草原蝗虫的生物学和生态学特征,揭示了其生活史、发生规律及空间分布格局,根据气象资料提出了预测预报的方法。     

草原蝗虫生物学和生态学的研究

论述了草原蝗虫的生物学和生态学特征,揭示了其生活史、发生规律及空间分布格局,根据气象资料提出了预测预报的方法.     

Ecology,Osmoregulation and Reproductive Biology of the White Steenbras,Lithognathus Lithognathus (Teleostei: Sparidae)

Over a one-year period 437 steenbras, Lithognathus lithognathus, ranging from 8-39 cm fork length were sampled from the Heuningnes River Estuary. The length-weight relationship was linear and there was no fluctuation in the modal size range throughout the year. Steenbras up to the age of six years and over inhabited the estuary, adapting to large salinity fluctuations. Abundance of food items, mainly Crustacea and Annelida, and virtual absence of predators made the estuary an ideal nursery ground. Ectoparasitic infestation by leeches and copepods was moderately intense without causing any apparent deleterious effects.

In a series of experiments designed to study osmoregulation in steenbras, it was found that haematocrits from fish sampled after 48 hours in freshwater were significantly (P<0,01) higher than the seawater controls. Two of the five protein fractions, however, as well as total protein, chloride, sodium, potassium and osmolality were all significantly (P<0,01) decreased in freshwater. Steenbras were unable to survive more than one week in freshwater. Due to capture diuresis the plasma constituents from a freshly captured sample were all significantly (P<0,01) higher when compared to steenbras acclimated for 48 hours in seawater.

Gonads from the entire estuarine sample were all infantile, virtually impossible to sex and showed no macroscopic signs of development. Histology of a representative sample showed them to be all hermaphroditic, with mainly testicular-dominant ovotestes. Maturity indexes assigned on the basis of ovarian and testicular development gave an indication of a cyclic rhythm in activity during pre-maturation, with a June peak. Marine steenbras ovotestes, on the other hand, were large and could be accurately sexed macroscopically. Histology of 42 gonads again revealed a majority of testicular-dominant hermaphroditic ovotestes. Maturity indexes indicated peak activity in June and a minimum in September, suggesting a spawning period in July and August.

Sex-chromatin (Barr) bodies were detected in liver nuclei of ovarian-dominant ovotestes, but were almost entirely absent from testicular-dominant ovotestes. Prediction of the genetic sex against the actual dominant macroscopic sex, based on the presence or absence of Barr bodies in a sample of steenbras liver sections proved very accurate. This is the first record of sex-chromatin occurring in teleost tissue.

There was no indication of sex-reversal, the steenbras remaining permanently hermaphroditic throughout the study year. It is postulated that the steenbras is a rudimentary hermaphrodite with only one of the two sexes functioning throughout the individual's life span. This is possibly a transitionary stage towards eventual gonochorism.     

类鼻疽杆菌生态学研究

在实验室条件下，进行类疽杆菌在不同温度，ＰＨ，湿度及不同类型土壤和水中的存活试验，类鼻疽杆菌与水、土壤分离菌的干扰试验，结果表明，类鼻疽杆菌对温度，湿度，紫外线较为敏感，而其他外界条件因素对其影响较小，对营养要求较低，因此该菌有较强的环境适应性，在自然中只要满足其基本需求即为广泛，长期生存而形成自然疫源地。     

草原毒草白喉乌头的遗传多样性与遗传结构研究

通过测定采自天山和阿尔泰山草原的17个白喉乌头居群的叶绿体DNA片段序列,调查了其遗传多样性和空间遗传结构,并计算出每个居群的遗传多样性;运用分子变异方差(AMOVA)分析计算发生在居群内和居群间的遗传变异比例;利用错配分析来检验该物种是否发生了历史居群扩张;最后,基于最大熵方法模拟其物种在不同时期的分布区。结果表明:白喉乌头具有较低水平的遗传多样性(单倍型多样性±SD=0.343 7±0.048 8),所有居群均共享一个单倍型;遗传变异大致均等分布于居群间和局群内(58.25%vs.41.75%);两个不同谱系的分化发生在第四纪冰期(1.816~2.280百万年以前)末次盛冰期时期,该物种的避难所存在于天山西部,而在未来气候变化条件下其分布区不会发生变化。研究认为白喉乌头这种空间遗传结构与其克隆繁殖、长的生活周期、异交繁殖等生活史特征,以及第四纪气候变化影响相关。     

瑞香狼毒生物学生态学研究进展

瑞香狼毒是我国天然草地重要的毒害草之一,其地理分布贯穿我国大部分草原地区,北自内蒙古高原东部、南至青藏高原西部和云贵高原,是一种分布范围极其广泛的多年生草本植物。近年来,由于天然草地持续退化,瑞香狼毒在退化草地上的扩散日益严重,影响我国草地畜牧业的可持续发展与生态安全。本文综述了近20年来我国学者在瑞香狼毒生物学、生态学以及化学防除效果方面的研究进展,以期全面了解这种重要的毒害草,为瑞香狼毒的防除、维持草地生产力和生物多样性提供理论依据。